非线性渗流对异常高压气藏产能的影响

Influence of non-liner flow on productivity of abnormal high pressure gas reservoir

异常高压低渗透气藏的开发过程除受到应力敏感效应的影响外,还受到启动压力梯度的影响。针对这种气藏的特殊渗流特征,推导了考虑应力敏感效应、启动压力梯度和同时考虑二者的渗流微分方程,并以某异常高压低渗透气藏为例,研究了应力敏感效应和启动压力梯度对异常高压低渗透气藏产能的影响。研究结果表明,应力敏感效应和启动压力梯度对异常高压低渗透气藏的开发效果有显著影响,考虑应力敏感效应和启动压力梯度的异常高压低渗透气藏渗流微分方程对研究此类气藏的渗流特征具有一定的指导意义。

The development of abnormal high pressure and low permeability gas reservoirs is not only affected by stress sensitivity but also influenced by start-up pressure gradient.In view of the particular flow characteristics of this kind of gas reservoir,three flow differential equations are derived which take stress sensitivity,start-up pressure gradient and both of them into account.Furthermore,taking an abnormal high pressure and low permeability gas reservoir as an example,we studied the effects of stress sensitivity and start-up pressure gradient on the productivity.The results show that stress sensitivity and start-up pressure gradient have a great impact on the development of abnormal high pressure and low permeability gas reservoirs,and the flow differential equations for this kind of reservoir considering stress sensitivity,start-up pressure gradient and both of the two,have some guidance for the study on flow characteristics of this kind of reservoir.